Sofa



FIG. 1 is a perspective view of the sofa showing my new design;

FIG. 2 is a side elevation view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a top plan elevation view thereof;

FIG. 5 is a back view thereof; and,

FIG. 6 is a bottom plan view thereof. 

The ornamental design for a sofa, substantially as shown. 